/* style.css */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

:root {
    --primary: #4361ee;
    --secondary: #4cc9f0;
    --accent: #7209b7;
    --text: #2b2d42;
    --light: #f8f9fa;
    --glass: rgba(255, 255, 255, 0.2);
    --border: rgba(255, 255, 255, 0.3);
    --shadow: 0 8px 32px rgba(31, 38, 135, 0.15);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Noto Sans SC', sans-serif;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    color: var(--text);
    min-height: 100vh;
    overflow-x: hidden;
    padding: 0;
}

.background-blur {
    position: fixed;
    top: -50px;
    left: -50px;
    right: -50px;
    bottom: -50px;
    background: url('');
    filter: blur(40px);
    z-index: -1;
}

/* 玻璃拟态效果 */
.glass {
    background: var(--glass);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    border-radius: 20px;
    overflow: hidden;
}

.glass-input {
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 14px 20px;
    font-size: 16px;
    color: var(--text);
    transition: var(--transition);
}

.glass-input:focus {
    outline: none;
    background: rgba(255, 255, 255, 0.25);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.3);
}

/* 导航栏 */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    margin: 1rem;
    position: relative;
    z-index: 100;
}

.logo {
    display: flex;
    align-items: center;
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.logo-icon {
    margin-right: 10px;
    animation: float 3s ease-in-out infinite;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 2rem;
}

.nav-links a {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    padding: 8px 0;
    position: relative;
    transition: var(--transition);
}

.nav-links a:after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: 0;
    left: 0;
    background: var(--primary);
    transition: var(--transition);
}

.nav-links a:hover:after,
.nav-links a.active:after {
    width: 100%;
}

.nav-links a.active {
    color: var(--primary);
}

.cta-buttons {
    display: flex;
    gap: 1rem;
}

.btn {
    padding: 0.7rem 1.5rem;
    border-radius: 12px;
    border: none;
    cursor: pointer;
    font-weight: 500;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
}

.btn-login {
    background: transparent;
    color: var(--text);
    border: 1px solid var(--border);
}

.btn-login:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.btn-signup {
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    color: white;
    box-shadow: 0 4px 15px rgba(67, 97, 238, 0.3);
}

.btn-signup:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(67, 97, 238, 0.4);
}

/* 主内容区域 */
main {
    max-width: 1400px;
    margin: 2rem auto;
    padding: 0 1.5rem;
}

.hero {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 3rem;
    margin-bottom: 4rem;
}

.hero-content {
    flex: 1;
    max-width: 600px;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    font-size: 1.4rem;
    font-weight: 300;
    margin-bottom: 2.5rem;
    color: #4a5568;
}

.cta-container {
    display: flex;
    gap: 1.5rem;
}

.btn-primary {
    background: linear-gradient(90deg, var(--primary), var(--accent));
    color: white;
    padding: 1rem 2.5rem;
    border-radius: 15px;
    font-weight: 600;
    font-size: 1.1rem;
    border: none;
    cursor: pointer;
    box-shadow: 0 5px 20px rgba(114, 9, 183, 0.3);
    transition: var(--transition);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(114, 9, 183, 0.4);
}

.btn-secondary {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
    padding: 1rem 2.5rem;
    border-radius: 15px;
    font-weight: 600;
    font-size: 1.1rem;
    cursor: pointer;
    transition: var(--transition);
}

.btn-secondary:hover {
    background: rgba(67, 97, 238, 0.1);
    transform: translateY(-3px);
}

.hero-image {
    flex: 1;
    position: relative;
    height: 400px;
}

.floating-element {
    position: absolute;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
}

.floating-element:nth-child(1) {
    width: 250px;
    height: 300px;
    top: 0;
    right: 0;
    background: linear-gradient(45deg, rgba(67, 97, 238, 0.1), rgba(76, 201, 240, 0.1));
    animation: float 6s ease-in-out infinite;
}

.floating-element:nth-child(2) {
    width: 200px;
    height: 240px;
    top: 50px;
    right: 260px;
    background: linear-gradient(45deg, rgba(114, 9, 183, 0.1), rgba(67, 97, 238, 0.1));
    animation: float 5s ease-in-out infinite 0.5s;
}

.floating-element:nth-child(3) {
    width: 180px;
    height: 180px;
    top: 200px;
    right: 150px;
    background: linear-gradient(45deg, rgba(76, 201, 240, 0.1), rgba(114, 9, 183, 0.1));
    border-radius: 50%;
    animation: float 7s ease-in-out infinite 1s;
}

/* 特性卡片 */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

.feature-card {
    padding: 2.5rem 2rem;
    text-align: center;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(31, 38, 135, 0.2);
}

.card-icon {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    background: linear-gradient(45deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text);
}

.feature-card p {
    font-size: 1.1rem;
    color: #4a5568;
    line-height: 1.6;
}

/* 登录模态框 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    justify-content: center;
    align-items: center;
    z-index: 1000;
    backdrop-filter: blur(5px);
}

.modal-content {
    width: 420px;
    padding: 2.5rem;
    position: relative;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.close-btn {
    position: absolute;
    top: 20px;
    right: 20px;
    font-size: 1.8rem;
    cursor: pointer;
    color: var(--text);
    transition: var(--transition);
}

.close-btn:hover {
    color: var(--primary);
    transform: scale(1.1);
}

.modal-content h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 1rem;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.remember-forgot {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.9rem;
    color: #4a5568;
}

.remember-forgot a {
    color: var(--primary);
    text-decoration: none;
}

.remember-forgot a:hover {
    text-decoration: underline;
}

.social-login {
    text-align: center;
}

.divider {
    display: flex;
    align-items: center;
    text-align: center;
    color: #718096;
    margin: 1.5rem 0;
}

.divider::before,
.divider::after {
    content: "";
    flex: 1;
    border-bottom: 1px solid #e2e8f0;
}

.divider::before {
    margin-right: 1rem;
}

.divider::after {
    margin-left: 1rem;
}

.social-icons {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
}

.social-btn {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: transparent;
    border: 1px solid var(--border);
    font-size: 1.2rem;
    cursor: pointer;
    transition: var(--transition);
}

.social-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-3px);
}

.signup-link {
    text-align: center;
    color: #4a5568;
}

.signup-link a {
    color: var(--primary);
    font-weight: 500;
    text-decoration: none;
}

.signup-link a:hover {
    text-decoration: underline;
}

/* 动画 */
@keyframes float {
    0% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-15px);
    }
    100% {
        transform: translateY(0px);
    }
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .hero {
        flex-direction: column;
        text-align: center;
    }
    
    .cta-container {
        justify-content: center;
    }
    
    .hero-image {
        margin-top: 3rem;
        width: 100%;
    }
}

@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .nav-links {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .hero-content h1 {
        font-size: 2.8rem;
    }
    
    .modal-content {
        width: 90%;
    }
}